Cyperus distans L. f., Cyperaceae

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Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Common name(s): [more details]

Chinese: shu sui suo cao

English: piedmont flat sedge, slender cyperus

Habit:  sedge

Description:  "Perennial, with small cormlike rhizome; culms solitary or few together, often rather slender, 35-100 cm tall, triquetrous, thickened at base; leaves shorter than culm; blades linear, 4-6 mm broad, weakly folded, herbaceous; sheaths rather elongated, light brown; corymb compound to decompound; leafy bracts 4-6, the lower 2 or 3 surpassing the corymb; rays 5-10, 1-15 cm long, patent; secondary corymbs with sort raylets or bearing 8-20 spikelets; spikelets divergent, linear, 8-40 mm long, 0.8-1 mm broad, cylindric, 8-32-flowered; glumes distantly disposed on a weakly zigzag rhachilla, elliptic, 1.8-2 mm long, obtuse at apex, membranous, sanguineous-brown on both sides, 3-5-nerved near keel, white-hyaline on upper margin, the keel greenish, hardly reaching the glume apex, the base decurrent along rhachilla, forming caducous white-hyaline wings; achenes oblong to oblong-elliptic, 3-sided, about 2/3 as long as glume, maturing dark brown, minutely punctulate; style short; stigmas 3; stamens 3" (Smith, 1979; pp. 247-248).

Habitat/ecology:  "A pantropical sedge occurring in wet grasslands and along waysides" (Wiggins & Porter, 1971; p. 802).

In Fiji, "probably a naturalized adventive...where it occurs near sea level on roadsides and cultivated land and in pastures" (Smith, 1979; pp. 247-248). In Papua New Guinea, "A weed of  roadsides, gardens, plantations and pastures; more troublesome in the wetter highland areas" (Henty & Pritchard, 1975; p. 31).

Propagation:  Seed

Native range:  Pantropical.

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Ecuador (Galápagos Islands) Galápagos Islands	Galápagos Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Fiji Fiji Islands	Viti Levu Island	introduced invasive	Smith, Albert C. (1979) (pp. 247-248) Vouchers cited: Greenwood 756, DA 8449, DA 9931, DA 8683, DA 3806, DA 7677, DA 8612, Greenwood 1104, DA 428
Guam Guam Island	Guam Island		Wagner, W. L./ Herbst, D. R./Weitzman, A./Lorence, D.H. (2013)
Palau Palau (Belau ) (main island group)	Babeldaob Island	native	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 66)
Palau Palau (Belau ) (main island group)	Koror (Oreor) Island	native	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 66)
Papua New Guinea Papua New Guinea (eastern New Guinea Island)	Papua New Guinea (eastern New Guinea Island)	invasive	Henty, E. E./Pritchard, G. H. (1975) (p. 31) In New Guinea, widespread, from low altitudes to over 2000 m.
Papua New Guinea Papua New Guinea (eastern New Guinea Island)	Papua New Guinea (eastern New Guinea Island)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Philippines Philippine Islands	Philippine Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Solomon Islands Solomon Islands	Solomon Islands	native	Hancock, I. R./Henderson, C. P. (1988) (p. 62)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia Australia (continental)	Queensland	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Cambodia Cambodia	Cambodia (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	Honduras (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	Nicaragua (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
China China	China (People's Republic of)	native	Zhengyi, Wu/Raven, Peter H./Deyuan, Hong (2013) Forests, swamps, grasslands, slightly dry or wet places on slopes, river margins, along trails; near sea level to 1800 m. Guangdong, Guangxi, Hainan, Xisha Qundao, Yunnan.
China China	Hong Kong	native	Wu, Te-lin (2001) (p. 309) In paddy fields and other wet places.
Indonesia Indonesia	Indonesia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Malaysia Malaysia	Malaysia (country of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Mexico Mexico	Mexico (United Mexican States)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013) Guerrero
Singapore Singapore	Singapore (Republic of)	uncertain if introduced invasive	Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 31) Weed of uncertain origin
South America (Pacific rim) South America (Pacific rim)	Colombia	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
South America (Pacific rim) South America (Pacific rim)	Ecuador (Republic of) (continental)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
South America (Pacific rim) South America (Pacific rim)	Perú (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Taiwan Taiwan Island	Taiwan Island	native	Zhengyi, Wu/Raven, Peter H./Deyuan, Hong (2013) Forests, swamps, grasslands, slightly dry or wet places on slopes, river margins, along trails; near sea level to 1800 m.
Thailand Thailand	Thailand (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Vietnam Vietnam	Vietnam (Socialist Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)

Indian Ocean
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Comoros Comoro Islands	Comoro Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
La Réunion (France) La Réunion Island	La Réunion Island	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Mauritius Mautitius Islands (Mauritius and Rodrigues)	Mauritius Island	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Seychelles Seychelles Islands	Seychelles Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)

Also reported from
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
United States (continental except west coast) United States (other states)	United States (other states)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013) North Carolina
United States (continental except west coast) United States (other states)	USA (Florida)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)

Control:  If you know of control methods for Cyperus distans, please let us know.